Control system for pipe lines



NOV. 21, 1939. L, HARLESTON I 2,180,901

CONTROL SYSTEM FOR PIPE LINES orneys Nov. 2,1, 1939.

L. HARLEsToN 2,180,901

` CONTROL SYSTEM FOR PIPE LINES I Filed April 7, 1958 2 Sheets-Sheet 2 -Byw Abm.

A orneys Patented Nov. 21, 1939 UNiTED STATES ATENT OFFICE l l 5 2,180,901 f j i .Y l;

CONTROL SYSTEM ron 1511er; Lnvsf "LoydjHarle'ston, Baton Rougafia'.

. Application April 17, 1938, semina 20,080' '5 Clanes.' '(01.' 13j-'4535' This invention relatesato a control rsystem vfor pipe lines, the .general object 'of the invention being to provide means for closing vthe-linewif 4a break should occur therein, to release-excessive pressure in a part of the line if a break yshould' occur in the line .and the pressure build up in anotherl part thereofand to trap 'fluid -in a line when the break occurs betweenthe invention and? the compressor station of the like.

This invention also .consists in certain other features of -construction and in thecombination and arrangement of the several parts to be hereinafter fully describedgillnstrated'1in the" accompanying drawings andspeci'cally In describing the invention in detail, reference will be had to the accompanying drawings where-v in like characters denote likefor corresponding parts throughout the several views, and in which-'z Figure 1 is aperspective view kof the invention. f'

ing the rack means. for operating the master."or main valve.

Figure 3 .is 1a, sectional view through the pressure diaphragm valve'. -Y I `Figure 4 is a .transversesectional the choke pipe.

Figure 5 is alongitudinal sectional View through said choke pipe. y v

Figure 6 is a sectional view through the triplel valve.

ernor valve.

tion P of 'the pipe line.

valveoasing and thestem-carries a toothed lgear or part 2 which is engaged by a rack lbar "3 con# `nected lto a rodwhich in turn is'connected'to v a piston located in vthe cylinderl 5 so that move'- ment of the piston in the cylinder will open 'andi close the valve. A vertically arranged vpipe line f5 rises from the section P and has a gauge YI lait its upper end, uid to whichisl controlled byqa valve 8 and a second vertically arranged pipe line 9 rises from'the se'ction'Pfand has a` gauge llin communication therewith through 'the pipe Il which contains avalve 12. f-lBoth ofthelinesf 6. and 9 contain -the .valves I'Sa'd-jacenttheir lower ends. Alpipeline l`4 connectsthevertical ,f-mernberslf :andas together- 4.slightly above the 'pointed out -in` i the appended claims. v

Figure 2A is a fragmentary top :plan view-show-A view through vFigure 7 isa sectional view-"through the/gov# valves .i3 and lthis linecontains 1a valve l5 lad.jacent 4its connection with the vertical -member 9. Said pipe M is `connected withthe riser :S by .a chokeLp-ipe` lfwhich has azsmvallery bore than that .of .thetpipeflik asshown in.Figures 4 Iand .5; A pipe. line-IB connects Athe line M with one end of the cylinder' 5,. the i'luidpressure from-these f parts moving rthe `piston Ain said .cylinder 5 lin ya udirectionL-so. as to cause the rack -means. `to open the main valve A. This line i5 is provided`V the line- I-con-nects, with a port fof the triplevalve. iThis .line `2! is also providedrvvith .a gauge connection, 'part .2li

throughLthe line 20 into .the cylinder the .piston in the .cylinder .will be'moved to the -left so vas to close the main vvalve A. 1 A pipe liney 23 vhas one end connected to an upright partllfleadingl from the';right end. ofthe line" vlli and'having a discharge and.. gauge connectingipartz .atits upper Aend vcontrolled .by a valve12.6, .thek other fend of the line1231being connected with Sa" safety-valve' 21.on theupperend fof the'member, .a 'control valve 2B being.locatediinthe 1-ine.2.3':adjacent the pOintWhereitJOins `the safety vali/fel.v A vertical .pipe `line i'29iri'ses vfrom ra tank -30 andla .pipe line `3f! connectsithe upper end .of .the line 29 with the port v32ziof 4tl'lertriple .valve T.y

A pressure diaphragm valve 33 has its lower part :connected "bya pipelll'wvith 'the rvertical pipe line` .ii :above the `connection of thewchoke pipe I4" vwith sa'id .line-B :and va :pipe 315 connects .the opposite Yside of .the loweripart of this :valve 33' with an intermediate part of the veritioaliline 29. This pipe 3:5 connects to fa 'gaugel pipeI 3510i the vali/#e513 lwhich fcont'ai-ns the control v.valve 37. ,A governorvalve.38`has'1oneffside 'of its lower ipart 38 connected'by a Lpir'ieilwitli an upper portion of .the vertical line l29iand the vopposite lside of thelower Lpartloi this rvvalve 1'381i`s #connected v.by a pipe Ylinelll-zlwith -th'evtopof the -pre'ssure :diae-4 phragm valve f 33, `a valvell being 'located in Vthe line A'iad-j acent its1-connection Lwith the topo'f the valve .'33 andagauge pipe 42 isy connectedwith the line 40" above thevalve 51H land r'contains a y controlled .by .a valve 22. ,Thus ywhenthe fluid passes tromthe .triple valve.

valve 8. A pipe line 45 connects the inain pipe P with the tank or reservoir 30 and contains a regulator valve 46 and the tank or reservoir has connected therewith a gauge pipe 41 controlled by a valve 48.

The governor valve 38, triple valve T, safety valve 21 and the pressure diaphragm valve 33 as well as the main valve A are cf the usual or any desired construction and those shown are standard manufactured products.

The triple valve is shown in section in Figure 6 and is of the usual construction so it is not thought necessary to .describe the specic construction thereof. However, the major portions are described as follows. The slide valve is shown at 56 and is actuated by the stem of the main piston 5I which also controls the graduating valve 52 which controls the ow of air through service ports W and Z of the slide valve. The slide valve controls communication between pipe 20 and port 53 leading `to the atmosphere, between the pipe 3| and port 32 and the pipe 20 and port 20' and also between the pipe 3| and port 32 and the chamber above emergency plston 54. The main piston 5I controls the feed grooves 55. The emergency valve seat is shown at 56 andthe emergency valve at 51. A check valve is shown at 58 and itsV spring at 59. The graduating stem is' shown at 60 and its spring at 6|.

The governor valve is shown in Figure '1 and the valve in the lower part 38" thereof isshown at 62 anda spring 63 engaging the piston 64 connected with the stem of the valve, normally holds the valve in open position. A passage 65 leads from the upper part 38 of the valve to a point above the piston 64 and this passage is normally closed by means of a.V pin 66 carried by a diaphragm member 61 which is pressed downwardly by a spring 68. However, when air enters the space below the diaphragm member 61 through pipe 44 the diaphragm member is raised to lift the pin so that fluid can pass down the passage 65 and act upon the piston 64 to close the valve 62. .Y j

The pressure diaphragm valve is shown in section in Figure. 3 and the valve for controlling the passage of iiuid through the lowerv part thereof is shown at 16. This valve is normally held olf the seat by a spring 1| but when fluid enters "the top part of the pressure valve through pipe 40 the diaphragm 12 is depressed Awhich causes the stem 13 to .press downwardly upon the stem 14 to valve 10 so as to press said valve 10 upon .its seat, thus closing communication between the pipes 35 and 34.

Of coursewhen the .device is in operation all the valves for controlling the open gauge connections, as well as valve I5 are closed and with the fluid passing through the main line and there are no breaks in said line, Apressure from the main line passing through the line 44 from the upper part -of line 6 will lift diaphragm member 61 and pin 66 and some of the fluid will pass through the passage65 and act upon the piston 64 and thus close the valve 62 so that no pressure can pass from the tank or reservoiror from any'other part of the'vsystemV through the line 46 into the upper portion of the pressure diaphragm valve 33 and thus thespring 1I will hold the valve 10 in open position and some of the means to hold the `valveA vin open position. Some..

of the uid will pass into the triple valve through the line I9 and will ow past the main piston 5|, through the grooves and out of the port 32 into the line 3| and down the line 29 into the tank or reservoir 30. The reservoir is also connected to the line P' by means of the pipe 35, the lower part of the pressure diaphragm valve 33,

` pipe 34, and the lower part of riser6.

If the pressure in the main line should drop below a predetermined minimum for any reason, such as a break in section P ofthe main line, this minimum pressure in the part 38 of the governor valve 38 would permit the valve 62 Vin the lower section 38 of the valve 38 to open blocking the passage of the gas from the reservoir to the main line. This would cause the pressure from the reservoir to pass through the lines 29 and 3|, into the part 32 of the triple valve, which reverses the triple valve andy permits pressure fromthe reservoir to pass from pipe 3|, by

the slide valve of the triple valve into 1ine 20.

to the right hand end of cylinder 5 which forces the piston in'said cylinder to the left to close the main valve A. Pressure is released from the left hand end of the cylinder 5 through pipes I6, I4, I4 and 6 and through the breakin pipe P.

If the break is in the main line below the main valve and pressure should increase in the upstream section P, then when the pressure reaches a critical point or a predetermined point for which the safety valve 21 is set, then this increased pressure will open the safety valve 21 and the `iiuid passes into the line 23 and line` I9 through the triple valve so that the parts of the triple valveare returned to the position shown in Figure 6, which connects the right hand end of cylinder 5 with the atmosphere by Way of pipe 20 and the exhaust port 53 of the triple valve. Pipe I 4 acts as a choke so that the fluid coming from the safety valve builds up against this choke and goes through pipe I9 into the triple valve to operate the parts thereof. Some of this uid will pass through the line I4 and line I6 into the left hand end of cylinder 5 which causes the rack means to open the main valve, thus dumping the excess pressure into that part of the main line which has the break therein. In this case the device acts as a safety device to prevent excessivev pressure in a part of the main line from causing damage. As soon `as the pressure drops in said part of the main line, the

ksafety valve 21 closes and then the pressure in thereservoir acts to close the main valve A in the same manneras above described, due to the fact that the down stream section is open by the break therein.

In order that the reservoir will always have sufficient uid therein for closing the master valve after these safety valve openings, the small line 45 is provided for connecting the up-stream side of the main line to the reservoir, the regulator 46 permitting a small amount of fluid pressure to passinto the reservoir at all times.

In case the up-stream section of the main line should break, the dropping pressureat this point will also put the governor valve 38 into operation, thus causing the main valve A to close,

in the same manner as if a down stream section l hadA releasedgtheA pressure. ,This prevents the gas in the down stream section ofthe main line from backing up .and escaping through the break in the up-stream pressure.

The main Valve A may be opened or closed at any time without a break occurring in the main line, by an operator creating falsev pressures. The normal position of the main valve A is, of course, the open one. Therefore, if the operator wishes to close this valve he would close the small valve i3 in riser 6 which would block the pressure from the main line. valve 26 in the upper end of the line 24 tore? lease the positive pressure in the triple valve, `thus causing the triple valve to reverse so that the pressure from the reservoir 'will enter. the triple valve through line 3i and part 3 2 and then the reservoir pressure would now from the triple valve into line and into the right hand end of the cylinder 5 which causes the rack means to close the main valve. When the main valve is to be opened the small valve LS is opened .or small valve I3 which will permit the pressure to enter the triple valve through the line i9 and the pressure will pass from the -valve through the lines 3i and 29 into the reservoir which will take the pressure olf the piston of the cylinderv 5 at the right hand end thereof and applies the As will be seen this control goes into ,opera tion when the pressure declines to a predeter` mined pressure which would only happen in case that a line breaks. This system automatically closes the main line on each side of the break, provided an installation of the invention is set at intervals along the pipe line if an installation of the invention is installed between the break and the source of pressure, such as a gas well or compressor station, the device would close the main valvein the pipe line and act as la block gate for the main line. In case the source of pressure continues to build up pressure in eX- cess of the safety features of the line, then the small safety valve opens which in turn opens the master valve automatically and pumps the excess load through the pipe line. Thus in this case the device acts as a safety valve besides acting as a gate valve. Should the invention be below the break and the source of pressure, the invention. would close and trap what gas `or pressure is in the line below the invention and in this case it would act as a check valve also.

These devices are to be installed at predetermined distances on the main ow lines so that a break in the said lines between these points will operate these devices and thus block off the broken sections. As will be understood when vpressure comes in the triple valve through the pipe i9 the fluid cannot come out of the triple into the pipe 2B but must pass from the triple valve through 32 and thus pass into the reservoir. Outlet controlled by valve 2B serves as a gauge connection and also as an outlet to create a discharge of pressure to close the'valve A without a break occurring in the ow line. The emergency features of the triple valve will'come into operation when there is a tremendous drop or sudden drop in pressure in the ow line.

It is thought from the foregoing description that the advantagesiand novel features `of the invention will be readily apparent.

It is to be understood that changes maybe made in the construction and in the combination and arrangement of the several parts pro- Then he would open v vided that such .changes lfall vwithin the Vscope of the appended claims.

Having described the invention, what is claimed asnewis:' v v" 1. In `an apparatus of the class described,v a main line, a control valve in said line operative to open and close the same, valVeopera-ting mechanism including a cylinder and piston, the Alatter operative under pressure on opposite sides thereof to open and close said valve respectively,

and means to operate said piston comprising a pressure tank, a supplyline extending between the, main line and said tank, a return linel connecting the tank to said main line, a normally kopen cut-01T valve in the return linefor closing the same in the event of pressure failurein the main line, a cut-off valve control line connecting the tank with said ycut-off valve, a governor valve interposed in the. cut-off Valve control line and operative under pressure failure in the main line to closing of .the cut-ofi valve and Ithereby block the return line, a triple valve in the supply line operative under normal pressure in Ithe main line to open the supply line, a constantly open control line `for introducing pressure from the main line to one side of the'` piston, whereby the latter is operative in a direction to maintain the main valve open under normal pressure in the main line, a second control line from the triple valve to the opposite side of the piston and controlled by the triple valve to exhaust from said side of the piston under normal pressure in the main line, said triple valve beingv operated by pressure in the tank when the returny line is closed to establish communication be-v latter operative under pressure onopposite sides thereof to open and close said valve respectively,

and means to operate said piston comprising a pressure tank, a supply line extending between the. main line and said tank, a return line connecting the tank to said main line, a normally open cut-01T valve in the return line for closing the same in the event `of pressure failure in the main line, a cut-oi valve control line connecting the tank with said cut-off valve, a governor valve interposed in the cutoi`f valve control line and operative under pressure failure in the main line to closing of the cut-off valve and thereby block the return line, a triple valve in the supply line operative under normal pressure in the main line to open Ythe supply line, a constantly open control line for introducing pressure from the main line, said triple valve being operated by pressure in the tank when the return line is closed'to establish communication between said tank and the last-mentioned control line, whereby pressure isV introduced to said opposite side of the piston to cause the same tooperate the main Valve to closing position, a branch line having one end in communication with the main linel in advance of the control valve of the main line and its other end connected to that part of the supply line leading to the triple valve and a safety valve in the last-mentioned branch line.

3. In an apparatus of the class described, a main line, a control'valve in said line operative to open and close the same, valve operating mechanism including a cylinder and piston, the latter operative under pressure on opposite sides thereof to open and close said valve respectively, and means to operate said piston comprising a pressure tank, a supply line extending between the main line and said tank, a return line lconnecting 'the tank to said main line, a normally open cut-off valve in the return line for closing the same in the event of pressure failure in the main line, a cutoif valve control line connecting the tank with said cut-off valve, a governor valve interposed in the cut-off valve control line and operative under pressure failure in the main line to closing of the cut-oil valve and thereby block the return line, a triple valve in the supply line operative under normal pressure in the main line to open the supply line, a constantly open control line for introducing pressure from the main line to one side of the piston, whereby the latter is operative in a direction to maintain the main valve open under normal pressure in the main line, a second control line from the triple valve to the opposite side of the piston and controlled by the triple valve to exhaust from said side of the piston under normal pressure in the main line, said triple valve being operated by pressure in the tank when the return line is closed to establish communication between saidtank and the lastmentioned control line, whereby pressure is introduced to said opposite side of the piston to cause the same to operate the main valve to closing position, a branch line having one end in communication with the main line in advance of the control valve of the main line and its other end connected to'that part of the supply line leading to the triple valve and a safety valve in the lastmentioned branch line, a pipe connecting the l tank with the main line in advance of the control valve of the main line, and a regulator valve in the last-mentionedpipe.

4. In an apparatus of the class described, a main line, a control valve in said line operative to open and close the same, valve operating mechanism including a cylinder and piston, the latter operative under pressure on opposite sides thereof to open and close said valve respectively, a pair of pipes, one connected wth the main line in front of the control valve thereof and the other with the main line in rear of said control valve, a tank, a pipe connected therewith, a return pipe connecting the reservoir pipe to the rear pipe connected with the main line, a normally open valve in the return pipe, pressure actuated means for closing said valve, a pipe leading from the tank pipe to the pressure means, a normally open valve in the last-mentioned pipe, pressure means for closing the last-mentioned valve, a line connecting the pressure means to the rear pipe for holding the Valve closed by the pressure from the said rear pipe, a choke pipe connected wth the rear pipe, a triple valve, a line connecting the outer end of the choke pipe with the main port of the triple valve and acting to hold the valve in release position by normal pressure from the main line, a line connecting the outer end of the choke pipewith the front pipe which is connected with the main line, a line connecting the said connecting line with one end of the cylinder for causing pressure from the main line to hold the piston in valve opening position, a valve in said connecting pipe adjacent its point of connection with the front pipe, a pipe connecting a second port of the triple valve with the other end of the cylinder for connecting said end of the cylinder with the atmosphere when the triple valve is in release position, a line connecting the third port of the triple valve with the tank pipe for supplying fluid to the reservoir from the main line when the triple valve is in release position, the tank pressure acting to reverse the triple valve when the valve in the return line is closed, whereby uid is supplied to said end of the cylinder to cause the piston to close the valve in the main line.

5. In an apparatus of the class described, a main line, a control valve in said line operative to open and close the same, valve operating mechanism including a cylinder and piston, the latter operative under pressure on opposite sides thereof to open and close said valve respectively, a pair of pipes, one connected with the main line in front of the control valve thereof and the other with the main line in rear of said control valve, a tank, a pipe connected therewith, a return pipe connecting the reservoir pipe to the rear pipe connected wth the main line, a normally open valve in the return pipe, pressure actuated means for closing said valve, a pipe leading from the tank pipe to the pressure means, a normally open valve in the last-mentioned pipe, pressure means for closing the last-mentioned valve, a line connecting the pressure means to the rear pipe for holding the valve closed by the pressure from the said rear pipe, a choke pipe connected with the rear pipe, a triple valve, a line connecting the outer end of the choke pipe with the main port of the triple valve and acting to hold the valve in release position by normal pressure from the main line, a line connecting the outer end of the choke pipe with the front pipe which is connected with the main line, a line connecting the main connecting line with one end of the cylinder for causing pressure from the main line to hold the piston in valve opening position, a valve in said connecting pipe adjacent its point of connection with the front pipe, a pipe connecting a second port of the triple Valve with the other end of the cylinder for connecting said end of the cylinder with the atmosphere when the triple valve is in release position, a line connecting the third port of the triple valve with the tank pipe for supplying fluid to the reservoir from the main line when the triple valve is in release position, the tank pressure acting to reverse the triple valve when the valve in the return line is closed, whereby iluid is supplied to said end of the cylinder to cause the piston to close the valve in the main line, a safety valve connected with the front pipe, a line connecting the safety valve with the pipe which connects the choke pipe with the lcylinder and a manually operated valve in a part of the pipe connected with the safety valve for opening said pipe to the atmosphere.

LOYD HARLESTON. 

